A man who has admitted burying his ex-girlfriend in an Odessa oilfield after killing her here has been charged with murder, Houston police say.

Mark Augustin Castellano, 37, faces charges in the September 22 murder of Michelle Warner, 31, who was last seen in the 7200 Bellerieve on that day. (Castellano talked with TV's Dr. Phil before owning up to the murder, spinning a tale that Warner had walked out.)

Family members said she had fought with her ex-boyfriend and they filed a missing persons report; Castellano allegedly took off for relatives in Odessa with the couple's three-year-old son.

Investigators kept in touch and interviewed him Sunday, HPD says:

During the interview, he admitted to his role in Warner's death and leaving her body in the couple's apartment. Castellano stated he drove his son to Odessa, left him with relatives and returned to Houston to retrieve Warner's body. He then drove back to the Midland-Odessa area where he attempted to bury her body in an oilfield.